One or more embodiments of the invention generally relate to compositions having insect repellent effect. More particularly, certain embodiments of the invention relates to compositions that include esters based on terpenoids and neurotransmitter amino acids having insect repellent effect.
The following background information may present examples of specific aspects of the prior art (e.g., without limitation, approaches, facts, or common wisdom) that, while expected to be helpful to further educate the reader as to additional aspects of the prior art, is not to be construed as limiting the present invention, or any embodiments thereof, to anything stated or implied therein or inferred thereupon. Arthropods are typically considered to be dangerous vectors of deadly pathogens and parasites, and are believed to be a key threat to millions of people around the world. They are believed to transfer malaria pathogens, yellow fever, dengue fever, West Nile, Chikungunya virus, filariasis, Zika virus and others. Research is ongoing in the pharmaceutical industry for new compositions having insect repellent effect. The following is an example of a specific aspect in the prior art that, while expected to be helpful to further educate the reader as to additional aspects of the prior art, is not to be construed as limiting the present invention, or any embodiments thereof, to anything stated or implied therein or inferred thereupon. By way of educational background, another aspect of the prior art generally useful to be aware of is that monoterpenoids have been developed and studied as insecticides for many years, however, their mode of action is not yet very clear. Monoterpenoids may act on various targets in insects, especially on the nervous system, including γ-aminobutyric acid (GABA)-gated chloride channels, octopamine receptors, tyramine receptors, acetylcholine esterase, nicotinic acetylcholine receptors (nAChR), sodium channels, and possibly other methods. The different monoterpenoids are believed to bind to ionotropic GABA receptors in insects. Thymol, linalool, menthol, camphor, carvone, borneol, and other monoterpenoids were shown to be positive allosteric modulators of insects' GABA receptors. G-protein-coupled receptors in insects including octopamine receptors and tyramine receptors are also believed to be candidate targets for monoterpenoid insecticides. Carvacrol, alpha-terpineol, pulegone, eugenol, and about twenty other monoterpenoids were demonstrated to have binding activities at an octopamine receptor from American cockroach with high sensitivities. They were either antagonists or agonists of the octopamine receptor.
In view of the foregoing, it is clear that these traditional techniques are not perfect and leave room for more optimal approaches.